Apparatus for making dished heads



Patented 13, 1931 PATENT oFFicE- UNITED STATES crimes 3. cusnwa, or YOUNGSTOWN, onro, assrenoa 'ro THE commnncrar. sumame a s'rmrme comrm, or YOUNGSTOWN, 01110, A conronarron or 01110 APPARATUS FOR MAKING DISHED HEADS Application filed larch 15, 1926. Serial No. 94,724.

This invention relates to the making of dished metal heads from sheet metal, and is particularly valuable in the manufacture of large sized metal heads, such as are used for tank cars and the like.

Small metal heads have been made out of ductile materials, such as copper, by spinning a flat sheet over a form into the desired shape, but this practice has not been followed in the working of ferrous material, such as sheet iron or steel, because of the entirely different properties of the metal. The general practice in making a lar e dished head out of sheet steel has been to rst form a circular blank and then roughly flange the same at a red heat. The flanged blank is then reheated and placed between dies that dish the head'as desired. It has been necessary to then square up the flange in order to produce a finished head.

I provide for flanging the edge of a blank and then progressively dishin the blank from the center thereof towar the flange. The operation is preferably carried out at a single station by first clam ing the center portion of a substantially at blank, then rounding the same, then flanging the blank while leaving it clamped, and while still maintaining the center clamped, progressively working the metal from the center to the flange into dish form. With this process the heatlng and reheating operations and the squaring up or trimming of the flange are done away with.

In the accompanying drawings, which illustrate diagrammatically the steps in the making of a dished head according to my invention,-

Figure 1 is a vertical section through an apparatus for carrying out my improved method of making dished heads; and

Figures 2, 3, 4 and 5 are'similar views to reduced scale showing successive steps in the operation. I

In the illustrated embodiment of the invention there is shown a former 2 mounted on a rotatable support 3. A rotatable clamp member 4 is provided, and this is movable toward and away from the former 2. A sub:-

stantially flat plate 5 is clamped between the former 2 and the clamp member 4.

When the flat plate 5 is thus clamped it is supported near its edges by a supporting ring 6, but it overhangs this ring in an amount depending on the Width of the flange to be provided on the head. The supporting ring 6 is provided with supporting arms 7 and is arranged to be moved vertically with respect to the form 2. The ring 6 rotates with the form 2.

When the sheet 5 is first clamped, it will generally be non-circular with respect to the axis of rotation of the form 2, and may even be a rectangular plate. A cutting tool 8 is first applied for rounding the plate by removing the excess metal 9. One or more flanging tools, such as 10, are then applied to the overhanging edge of the plate and there is produced a flat flanged plate such as shown in Figure 2. It will be noted that the flange is of a width substantially corresponding to the amount the flat plate 5 overhung the ring 6 after being rounded.

The head is dished by workingthe metal progressively from the center toward the flange, which is indicated by the reference character 11. The dishing is accomplished by one or more tools 12 adapted to bear against the metal and force it onto the top of the form 2 while progressively moving outward toward the flange 11. As the tools 12 move outwardly the supporting ring 6 is lowered, so that at an intermediate stage of the operation the tank head appears as shown in Figure 3.

When the tools 12 have reached the periphery of the form 2, the head is as shown in Figure 4, but it is preferred that the forming tools be moved still further outwardly and the supporting ring 6 still further lowered, as shown in Figure 5. This eflectually carries the curvature of the head all the way out to the rim, as is desired.

Generally, there will be no further operations required on tank heads manufactured according to my invention. The numerous disadvantages of the old process are eliminated by my new process and apparatus. The

invention is not limited to the manufacture l of lar e dished heads, nor to the manufacture o dished heads from ferrous material, although certain features of the invention fwill:1 find their broadest application in such 1e p The term dished head is a term of definition and not of limitation, and is intended to include any article made fromsheet metal having a peripheral flange and a bulged portionwithin the flange. I have illustrated and described a preferred process and apparatus for carrying out my invention, but 1t will be understood that the invention is not limited to the form shown and described but may be otherwise embodied and practiced within the scope-of the following claims.

I claim:

1. Apparatus for making dished metal heads, including a form, means for supporting a blank thereon, means for rounding the blank, means for flanging the blank, and means for progressively working the metal from the central portion of the form toward the flange.

2. Apparatus for making dished metal heads, including a form, a ring surrounding the same, a cutting tool adapted to round the blank, flanging means cooperating with the ring, and a dishing tool cooperating with the form and adapted to progressively work on the blank from the central portion thereof toward the periphery of the blank.

In testimony whereof I have hereunto set my hand..

CHARLES B. CUSHVVA. 

